18.1 Suggested Projects for Improving GNUdiff and patch

One should be able to use GNUdiff to generate a
patch from any pair of directory trees, and given the patch and a copy
of one such tree, use patch to generate a faithful copy of
the other. Unfortunately, some changes to directory trees cannot be
expressed using current patch formats; also, patch does not
handle some of the existing formats. These shortcomings motivate the
following suggested projects.